Jessie J says she's 'not ok' after surgery

Jessie J has revealed she's "not O.K." as she convalesces following surgery last week for a mystery illness.

The British singer last week canceled shows in Denmark, Belgium and her homeland after checking into hospital for a procedure.

She has since Instagrammed a picture of a drip in her arm with the message, "I am not ok... I am in a lot of pain." She continued, "But I'm working on it with the doctors" and she revealed the situation was "unexpected but I'm here trying my best to not let it win."

Precisely what she's undergone surgery for has yet to be revealed, though the singer last week shared a pair of pictures of herself in hospital garb, looking particular pale and unhappy in one of them. She then updated fans with the message, "After having an operation earlier this week, I am unfortunately suffering a longer recovery time than expected due to some problems that have occurred post the operation. I have been medically advised to cancel my shows this weekend. I am simply in no way to perform."

Jessie J is booked to play five shows in the next two weeks, beginning July 3 at Küçükçiftlik Park in Istanbul, Turkey. It's unclear yet whether she's fit to perform these shows.

Its unclear if her latest medical ailment is connected with the "sudden illness" that caused her to cancel the final three shows of her Australian tour in March. Back in 2012, she abruptly canceled a pair of shows in Australia citing "vocal exhaustion."

Curiously, the singer appeared on Sunday night's season opener of "The Voice Australia" and will return Monday. She's been enlisted as a judge for the season, which was pre-recorded months earlier for Channel 9.